Protracted emergence of overwintering Amyelois transitella (Lepidoptera: Pyralidae) from pistachios and almonds in California

The navel orangeworm, Amyelois transitella (Walker), is the primary insect pest of pistachios and almonds in California. Four years of research (2002-2006) were conducted in Madera and Kern Counties to elucidate the pattern of adult emergence of the overwintering navel orangeworm population. Springtime emergence from unharvested (mummy) nuts was protracted (600 degree-days or more from 1 January of each year) and in 2004 and 2006 extended to mid-July. The population structure, sex ratio, and timing of emergence differed between pistachio and almond mummies. Pistachio populations had a significantly greater proportion of late stage individuals compared with almond mummies, 85.7 versus 34.1%. The sex ratio of adults emerging from pistachio mummies was significantly skewed with a ratio 57:43 male:female compared with 50:50 in almond mummies. Emergence from mummies held outdoors (variable temperature) began in early March and continued through early June in both pistachio mummies and almond mummies. The adult emergence pattern from pistachio mummies contained a single emergence peak, whereas emergence from almond mummies occurred in multiple peaks. These same patterns occurred when mummies were held at constant temperature, and the emergence peak from pistachio mummies occurred sooner. The impact of these findings on understanding navel orangeworm population dynamics and current control recommendations is discussed.     

Depression of lymphocyte transformation and exacerbation of Behcet's syndrome by ingestion of english walnuts

Extracts of English and black walnuts, almonds and pecans stimulated increased incorporation of tritiated thymidine by cultured leucocytes from both normals and patients with Behcet's syndrome. English walnut extract also stimulated newborn cord blood leucocytes, indicating it to be a nonspecific stimulant. Within 2 days after ingestion of English walnuts by normals and patients with Behcet's syndrome, their in vitro lymphocyte reactivity to both the walnut extract and Candida antigens was significantly decreased. This inhibition of lymphocyte transformation may be more prolonged in the patients than in normal subjects and was associated with an increase in frequency and severity of their symptoms. Hypotheses relating the mechanism of action of these two apparently disparate phenomenon are discussed.     

Ex situ volatile survey of ground almond and pistachio hulls for emission of spiroketals: Analysis of hull fatty acid composition,water content,and water activity

The spiroketal conophthorin has recently been implicated as an important semiochemical of the navel orangeworm moth (Amyelois transitella), a major insect pest to California tree nuts. Additionally, new evidence demonstrates that fungal spores in the presence of linoleic acid produce conophthorin. Numerous investigations have analyzed the volatile emissions of almonds and pistachios under varying conditions, yet there are few reports of conophthorin as a volatile component. Previous studies by our laboratories have suggested almond hulls may be a source of conophthorin production. Accordingly, the volatile emissions of ex situ almond and pistachio ground hulls were surveyed at several developmental stages. Each ground sample was analyzed at various intervals to determine if conophthorin was produced. The almond and pistachio samples were presumed to have a natural fungal bouquet present. Additionally, the fatty acid composition, water content, and water activity of the hulls were analyzed for each sample. Conophthorin and the structurally similar compound chalcogran were detected from almond hulls and shells, but not from the pistachio samples. The almond and pistachio hulls were investigated for four fatty acid components – palmitic, oleic, linoleic, and linolenic. The fatty acid composition of almond hulls varied greatly throughout the growing season, whereas the composition of pistachio hulls remained relatively constant. Both water content and activity were constant in early stages of almond growth then dropped in the later stages of hull split. Spiroketal emission along with other associated volatiles is discussed. This is the first report of the fatty acid composition, water content, and water activity of developing almond and pistachio hulls.     

Effect of bait formulation and number of traps on detection of navel orangeworm (Lepidoptera: Pyralidae) oviposition using egg traps

Egg traps are the primary tool for monitoring egg deposition of the navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), and for timing treatments for this pest in almonds, Prunus amygdalus Batsch, and pistachios, Pistacia vera L. We compared, in almond and pistachio orchards, the number of eggs per trap in traps baited with almond meal, pistachio meal, or the current standard commercial bait. When considering cumulative eggs captured over an extended period, traps baited with pistachio meal prepared from previous-crop nuts generally captured a similar number of eggs compared with the commercial bait, and more eggs than those baited with almond meal prepared from previous-crop nuts. However, differences in eggs per trap between bait formulations were not as evident when examining individual weeks, particularly in weeks with few eggs per trap, as is typical when treatment decisions are made. The variance in eggs per trap was generally greater than the mean and increased with the mean and, when mean eggs per trap was low, most traps did not have eggs. We discuss implications of these findings for the relative importance of bait type and trap numbers for monitoring, and for experiments comparing egg trap performance.     

Aspergillus on tree nuts: incidence and associations

California exports tree nuts to countries where they face stringent standards for aflatoxin contamination. Trade concerns have stimulated efforts to eliminate aflatoxins and Aspergillus flavus from almonds, pistachios and walnuts. Incidence of fungi on tree nuts and associations among fungi on tree nuts were studied. Eleven hundred pistachios, almonds, walnuts and brazil nuts without visible insect damage were plated on salt agar and observed for growth of fungi. Samples came both from California nut orchards and from supermarkets. To distinguish internal fungal colonization of nuts from superficial colonization, half the nuts were surface-sterilized before plating. The most common genera found were Aspergillus , Rhizopus and Penicillium . Each species of nut had a distinct mycoflora. Populations of most fungi were reduced by surface sterilization in all except brazil nuts, suggesting that they were present as superficial inoculum on (rather than in) the nuts. In general, strongly positive associations were observed among species of Aspergillus ; nuts infected by one species were likely to be colonized by other species as well. Presence of Penicillium was negatively associated with A. niger and Rhizopus in some cases. Results suggest that harvest or postharvest handling has a major influence on nut mycoflora, and that nuts with fungi are usually colonized by several fungi rather than by single species. This revised version was published online in June 2006 with corrections to the Cover Date.     

Assessment of Changes in Some Biochemical Traits and Proteomic Profile of UCB-1 Pistachio Rootstock Leaf under Salinity Stress

Journal of Plant Growth Regulation - University of California at Berkeley I or UCB-1 pistachio rootstock is propagated from the cross between Pistacia integerrima male × Pistacia...     

Incidence of Aflatoxin in California Almonds

In a survey of California almonds, aflatoxin was found in 14% of 74 samples of unsorted, in-shell almonds as received by the processor in 1972, but it occurred at very low levels (below 20 parts per billion [ppb]) in 90% of the contaminated samples. The overall proportion of individual nuts contaminated was especially low and is estimated with 95% probability to have been in the range of 1 nut/55,300 nuts to 1 nut/14,700 nuts. Aflatoxin contamination is not restricted to any particular section of the almond-growing region of California. Commercial sorting procedures are effective in removing most aflatoxin-contaminated nutmeats, since none of 26 samples of processed, whole nutmeats contained aflatoxin. In contrast, 13 of 27 samples of diced almonds were contaminated, but nine of these 13 samples contained less than 20 ppb. Only one of 25 samples of sliced nutmeats contained aflatoxin (4 ppb). Thus, aflatoxin incidence in almonds varies greatly with the category of finished product. The apparent high incidence in diced nutmeats is probably due mostly to the more uniform distribution of aflatoxin occurring in this product (because of its small particle size) than that occurring in the other products. Sample size requirements for monitoring aflatoxin in almonds are discussed.     

In vitro metabolism of aflatoxin B1 by larvae of navel orangeworm, Amyelois transitella (Walker) (Insecta, Lepidoptera, Pyralidae) and codling moth, Cydia pomonella (L.) (Insecta, Lepidoptera, Tortricidae)

Larvae of the navel orangeworm (NOW), Amyelois transitella (Walker), a major pest of almonds and pistachios, and the codling moth (CM), Cydia pomonella (L.), the principal pest of walnuts and pome fruits, are commonly found in tree nut kernels that can be contaminated with aflatoxin, a potent carcinogen. The ability of larvae of these insects to metabolize aflatoxin B1 (AFB1) was examined. A field strain of NOW produced three AFB1 biotransformation products, chiefly aflatoxicol (AFL), and minor amounts of aflatoxin B2a (AFB2a) and aflatoxin M1 (AFM1). With AFL as a substrate, NOW larvae produced AFB1 and aflatoxicol M1 (AFLM1). A lab strain of CM larvae produced no detectable levels of AFB1 biotransformation products in comparison to a field strain which produced trace amounts of only AFL. Neither NOW nor CM produced AFB1-8,9-epoxide (AFBO), the principal carcinogenic metabolite of AFB1. In comparison, metabolism of AFB1 by chicken liver yielded mainly AFL, whereas mouse liver produced mostly AFM1 at a rate eightfold greater than AFL. Mouse liver also produced AFBO. The relatively high production of AFL by NOW compared to CM may reflect an adaptation to detoxify AFB1. NOW larvae frequently inhabit environments highly contaminated with fungi and, hence, aflatoxin. Only low amounts, if any, of this mycotoxin occur in the chief CM hosts, walnuts, and pome fruits. Characterizations of enzymes and co-factors involved in biotransformation of AFB1 are discussed.     

Seed predation and dispersal of glabrous filbert (Corylus Heterophylla) and pilose filbert (Corylus Mandshurica) by small mammals in a temperate forest, northeast China

We investigated the seed dispersal of glabrous filbert (Corylus heterophylla) and pilose filbert (Corylus mandshurica), two large-seeded shrub species in a temperate forest, northeast China, September 2006. Small mammals such as Apodemus speciosus, Clethrlonomys rufocanus, and Eutamias sibiricus, were regarded as the main dispersal agents. More seeds were harvested by small mammals in pilose filbert (98%) than in glabrous filbert (87.5%) till our last survey. Seed removal rates differed between the two species. Fewer seeds of glabrous filbert (17.5%) were eaten in situ than pilose filbert (57.5%). More seeds of glabrous filbert were removed (70%), stay intact after removal (25.5%), eaten after removal (16%) than pilose filbert. However, more seeds were cached after removal in pilose filbert than in glabrous filbert (10.5 and 4%, respectively). Fewer tagged seeds of pilose filberts (14%) were missed than glabrous filberts (24.5%). About 8 and 12 primary caches were found in glabrous filbert and pilose filbert seeds respectively, indicating scatter hoarding. All of the removed seeds were distributed within 10 m of seed stations for both filberts. The average dispersal distances for glabrous filbert did not differ from pilose filbert. Only a small proportion of the caches remained till our last survey (2 and 1%, respectively). Based on the results, we found a difference in dispersal patterns of glabrous filbert and pilose filbert seeds. Evidences showed that glabrous filberts might be a less preferred seed species for small seed-eating mammals compared with pilose filbert, probably due to its harder and thicker husk and low seed profitability.     

Effet des rayons gamma sur les larves de Plodia interpunctella (Lepidoptera: Phycitidae)

Résumé On peut envisager de protéger les produits emmagasinés tels que pistaches, noix, amandes, noisettes décortiquées, contre les détériorations dûes aux pullulations des larves et adultes de Plodia interpunctella (Lépidopt. Phycitidae), en irradiant ces produits avec des doses appropriées de rayons gamma. Nos expériences montrent que des doses de 10 Krads appliquées à des larves du dernier stade, prolongent la durée de la vie nymphale, réduisent le pourcentage d'émergence des imagos et provoquent chez les femelles une régression des ovaires. Ces effets sont encore plus marqués avec des doses de 12 et 14 Krads. Cette dernière dose pourrait être la dose optimum à envisager.

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Summary Protection of stored products such as pistachio nuts, walnuts, almonds and shelled hazel nuts against damage from infestation by larvae and adults of Plodia interpunctella (Lepidoptera: Phycitidae) by radiating these products with appropriate doses of gamma rays, can now be considered. Our tests show that doses of 10 krad applied to last-stage larvae prolong the length of pupal life, reduce the percentage of imaginal emergence and cause regression of the female ovaries. These effects are even more pronounced with doses of 12 and 14 krad. This last dose may well deserve the most attention.

     

Mycotoxins and mycotoxigenic moulds in nuts and sunflower seeds for human consumption

A survey was carried out to obtain data on the occurrence of mycotoxins and the mycotoxin-producing potential of fungi isolated from nuts (almonds, peanuts, hazelnuts, pistachio nuts) and sunflower seeds in Spain. Thin-layer chromatography was used to separate the toxins. Aflatoxins were detected in one sample of almonds (95 ppb aflatoxin B₁ and 15 ppb aflaxtoxin B₂) and in one sample of peanuts at a level below 10 ppb of aflatoxin B1. 100% of samples showed variable incidence of fungal contamination. The predominant fungi present in samples were Penicillium spp, Aspergillus niger, A. flavus, A. glaucus and Rhizopus spp. The results showed that isolates of different species were able to produce aflatoxins B₁, B₂, G₁, and G₂, sterigmatocystin, ochratoxin A, patulin, citrinin, penicillic acid, zearalenone, and griseofulvin.     

阿月浑子栽培品种生长及结实生物学特性研究

对来自美国和新疆的6个阿月浑子(Pistacia vera L．)品种的生长及结实生物学特性进行了研究。分析结果表明：Kerman和26—18^#品种嫁接后3年开花结实。品种与50年生黄连木亲和力较高,嫁接成活侏率和成活穗率达70％～100％,但品种在5月20日后有“回芽”现象。枝叶生长呈S型曲线,叶面积指数(LAI)平均达3．98。Kerman品种每个接穗3年后产果穗最高达31个,坚果和核仁发育正常,每个果穗上具坚果88．5～116个。单果重0．81～1．89g,出核率和出仁率分别为54．32％～55．0％和48．08％～59．09％。     

A site classification for Scottish native woodlands

Summary

The proposed site classification should assist in choice when creating or rehabilitating native woodlands on site types of different quality. Eight climatic zones are defined by warmth and wetness factors. Eight soil moisture regimes are defined by water table depth and the amount of available water in summer. Six soil nutrient regimes are defined by soil acidity and nitrogen availability. Woodland and scrub sub-communities of the National Vegetation Classification are ordinated by their preferences for soil moisture and soil nutrients, using Ellenberg ecological indicator values. After stratification by climatic zone, the communities are then located on the grid of soil moisture and nutrient regimes. The actual and relative positions of the communities and sub-communities are discussed in relation to existing knowledge of their distribution in relation to climate and soil types.     

Evaluation of monitoring traps with novel bait for navel orangeworm (Lepidoptera: Pyralidae) in California almond and pistachio orchards

Experiments conducted in three almond, Prunus dulcis (Rosales: Rosaceae), orchards and three pistachio, Pistacia vera (Sapindales: Anicardiaceae), orchards in 2009 and 2010, and determined that sticky bottom wing traps baited with ground pistachio mummies, or a combination of ground pistachio plus ground almond mummies, trapped more adult female navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), than did traps baited with ground almond mummies alone. During both years of this study, 2.9 and 1.8 more moths were caught in traps baited with pistachio mummies compared with traps baited with almond mummies in almond orchards and pistachio orchards, respectively. Also, traps located in pistachio orchards caught 5.9 and 8.3 times more navel orangeworm than were trapped from almond orchards in 2009 and 2010, respectively. Implications for use of this novel baited trap in almond and pistachio orchard integrated pest management programs are discussed.     

The Cyperaceae within Nigeria—distribution and habitat

The Nigerian Cyperaceae are divided into five groups on the basis of individual species distribution patterns, the groups being subdivided into sections according to the habitats in which the species usually occur. Lists of the species are given, indicating known examples and herbaria where they are housed. Of the groups, one contains widely distributed species; the remaining four contain those related to rock type, elevation, climatic conditions and maritime conditions. Longevity and seasonality are briefly discussed in relation to habitat and distribution. The groups are considered in relation to the generally accepted concept of vegetational zonation within Nigeria; and the apparent importance of parent rock type for a large number of sedges and absence of a major vegetation type related to this are noted.     

Distribution of twelve moist forest canopy tree species in Liberia and Côte d'Ivoire: response curves to a climatic gradient

Abstract. The occurrence and abundance of 12 canopy tree species from the moist tropical forests of West Africa have been studied in relation to a climatic gradient. We focused on environmental factors related to water availability: annual amount of rainfall, the length of the dry season, and cumulative water deficit. Species occurrence and abundance data are used for 39 forest sites in Liberia and southwest Côte d'Ivoire. Species responses are modelled using a set of five increasingly complex models, ranging from a no-trend model to a skewed bell-shaped response curve. The study species show different distribution patterns. Most of them suggest a close relationship to climatic conditions. Fitting of species occurrence data to each of the three climatic factors results in most cases in simple models. In only one out of 36 cases a bell-shaped response curve is needed to describe the data. Four of the 12 species show no response to the climatic factors when only occurrence is evaluated. When abundance data are used, in 33 of the 36 cases significant response models are found. In general these are much more complex than in the cases of species occurrence data: in 10 of the 36 cases a bell-shaped response model is found to describe the data best. This is in contrast with the widespread belief that species response curves are bell-shaped: within the forest zone in the area studied this is not generally the case. The importance of the three climatic factors for the distribution of the species is evaluated: for four species mean annual rainfall is the most important variable, for four species the length of the dry period, and for one species cumulative water deficit. Consequently, the assumption that mean annual rainfall is the most important factor determining tree species distribution in West African forests is not correct. Species response models to climatic factors show where species have their geographical optima. Implications for forest management are briefly discussed.     

The distribution of epiphytic orchids in Nigeria in relation to each other and to geographic location and climate, type of vegetation and tree species

The epiphytic orchids of 31 sites in Eastern, Midwestern, Western and Northern Nigeria are enumerated. The distribution of these 109 species of orchids is related to geographic location and to the environmental factors: climate, vegetation type, most common tree species. Distribution is further discussed in relation to variation within species. An hypothesis of a former more or less continuous orchid population fragmented by climatic shifts toward dryness, by erosion and land level sinkage, and by change of vegetation brought about by man, is advanced. It is suggested that, with such fragmentation, the orchids are now in a phase of rapid speciation and evolutionary development.     

Nitric oxide fumigation for control of navel orangeworm,Amyelois transitella,on walnut

The navel orangeworm (NOW), Amyelois transitella (Walker), is a major post-harvest pest of tree nuts including walnut, almonds and pistachios. Nitric oxide (NO) was recently discovered to be a potential fumigant under ultralow oxygen conditions for post-harvest pest control. In this study, NO fumigation was evaluated for efficacy against eggs, larvae and pupae of NOW. NO fumigation was found to be similarly effective against NOW on artificial diet and in infested walnuts. Fumigations of 4, 8 and 16 hr with 2.0, 1.0 and 0.5% NO, respectively, achieved complete control of small and large larvae in artificial diet. Complete control of pupae on artificial diet was achieved in 8, 16 and 24 hr fumigations with 2.0, 1.0 and 0.5% NO, respectively. For NOW in infested walnuts, complete control was achieved in 6, 8 and 16 hr fumigations with 1.5, 1.0 and 0.5% NO, respectively, for small larvae; in 4-, 8- and 24-hr fumigations with 2.0, 1.0 and 0.5% NO, respectively, for large larvae; and in 8-, 16- and 24-hr fumigations with 2.0, 1.0 and 0.5% NO, respectively, for pupae. Eggs were more tolerant to NO fumigation than larvae and pupae, and complete control of NOW eggs was achieved in 8- and 16-hr fumigation with 3.0 and 2.0% NO, respectively. This study demonstrated the efficacy of NO fumigation against NOW on walnut and its potential as an alternative post-harvest treatment for the pest.     

Impact of climatic change on bog ecosystems,with special reference to sub-oceanic raised bogs

The relation between climatic conditions and type of peatland ecosystem in the different climate zones in Europe is discussed. Special attention is given to the hydrology of raised bogs in the sub-oceanic region. Possible effects of climatic change on such raised bog systems are discussed in terms of changes in water discharge, ground-water table, rate of peat accumulation, and flora and vegetation. It is concluded that future changes, as suggested by the more widely accepted scenarios for climatic change, will seriously disrupt the ecological functioning of these peatland ecosystems, and it is doubtful whether at least the most southerly examples of sub-oceanic raised bogs will at all survive. Finally, suggestions are given for future research on the impact of climatic change on peatland ecosystems.     

Underground temperature and inferred climatic temperature of the past millenium

There is considerable evidence from different fields of investigation that the world climate has undergone significant variations, even during the last 1,000 years. The effect of the change of temperature on the earth's surface in the past may be preserved at depths of several hundred feet below the surface. The relation between underground and surface temperature is the reaction of the internal field in a semi-infinite medium to the boundary conditions. Any change at the surface is propagated downwards, and it is shown that the detailed record of temperature with depth can be used to trace the past climatic history. The theory of climatic correction of heat flow is used, and the data is obtained from two boreholes in northeastern Ontario. After analysis the measured underground temperature clearly confirmed the notably warm climate that lasted a few hundred years around A.D. 1000–1200 and the following cold period after 1500.